AUTHOR=Meloni Giovanni , Giustini Andrea , Park Heejune 

TITLE=CO2 Activation Within a Superalkali-Doped Fullerene

JOURNAL=Frontiers in Chemistry

VOLUME=9

YEAR=2021

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2021.712960

DOI=10.3389/fchem.2021.712960

ISSN=2296-2646

ABSTRACT=<p>With the aim of finding a suitable synthesizable superalkali species, using the B3LYP/6-31G* density functional level of theory we provide results for the interaction between the buckminsterfullerene C<sub>60</sub> and the superalkali Li<sub>3</sub>F<sub>2</sub>. We show that this endofullerene is stable and provides a closed environment in which the superalkali can exist and interact with CO<sub>2</sub>. It is worthwhile to mention that the optimized Li<sub>3</sub>F<sub>2</sub> structure inside C<sub>60</sub> is not the most stable C<sub>2v</sub> isomer found for the “free” superalkali but the D<sub>3h</sub> geometry. The binding energy at 0 K between C<sub>60</sub> and Li<sub>3</sub>F<sub>2</sub> (D<sub>3h</sub>) is computed to be 119 kJ mol<sup>−1</sup>. Once CO<sub>2</sub> is introduced in the endofullerene, it is activated, and the <inline-formula id="inf1"><mml:math id="minf1" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mover accent="true"><mml:mrow><mml:mi>O</mml:mi><mml:mi>C</mml:mi><mml:mi>O</mml:mi></mml:mrow><mml:mo stretchy="true">^</mml:mo></mml:mover></mml:mrow></mml:math></inline-formula> angle is bent to 132<sup>°</sup>. This activation does not follow the previously studied CO<sub>2</sub> reduction by an electron transfer process from the superalkali, but it is rather an actual reaction where a F (from Li<sub>3</sub>F<sub>2</sub>) atom is bonded to the CO<sub>2</sub>. From a thermodynamic analysis, both CO<sub>2</sub> and the encapsulated [Li<sub>3</sub>F<sub>2</sub>⋅CO<sub>2</sub>] are destabilized in C<sub>60</sub> with solvation energies at 0 K of 147 and &lt; −965 kJ mol<sup>−1</sup>, respectively.</p>